What is b12 deficiency?

The immune system normally makes antibodies to attack bacteria and viruses. Pernicious anaemia is caused by an autoimmune disease, which causes the immune system to make antibodies against other parts of your body. In pernicious anaemia, antibodies are formed that attack the stomach lining and damage the cells that produce intrinsic factor. This stops intrinsic factor from attaching to B12, and so the vitamin cannot be absorbed into your body.

b12 deficiency information from trusted sources:

B12 deficiency

Your body needs vitamin B12 in order to create red blood cells and keep the nervous system healthy. It is also needed to absorb folic acid and it helps to release energy. B12 is absorbed through your intestines from a variety of foods, but mainly meat, fish and dairy products. It can be stored in the body in small amounts, and around 80% of this is stored in the liver. It may take three or four years for the symptoms of deficiency to develop.

Pernicious anemia, vitamin B12 deficiency

Contents

Diagnosis

Your GP will normally carry out a physical examination to look for signs of vitamin B12 deficiency, such as a rapid pulse and pale skin. A blood test may be taken to check the number and appearance of red blood cells. People with a B12 deficiency have large red blood cells that look unusual. Laboratory tests can also be used to measure the level of vitamin B12 in the blood.

Strict vegetarians (who do not eat eggs) and vegans can help to prevent B12 deficiency by choosing breakfast cereals fortified with B12, and taking mineral supplements. Most people should be able to get all the B12 they need by eating a balanced diet containing meat, fish and dairy foods.

Vitamin B12 is needed by all cells of the body in order to allow them to multiply. A shortage of vitamin B12 mainly affects red blood cells, because millions need be made every minute. A lack of red blood cells can lead to anaemia. The common symptoms of anaemia are tiredness, shortness of breath and palpitations.

B12 deficiency is treated with a course of vitamin injections. A form of vitamin B12 known as hydroxocobalamin is injected into a muscle once every two to four days. Around six injections are given, which is enough to build up a store of vitamin B12 in the body.